Craniofacial morphology in Turner syndrome karyotypes

Abstract

Introduction:A complete or partial absence of an X chromosome in the karyotype of phenotypic females has an impact on craniofacial morphology. The aim of this study was to determine the characteristics of the craniofacial complex in patients with Turner syndrome (TS), and to evaluate the influence of various karyotypes on craniofacial morphology. Materials and methods:The study population was comprised of 40 TS female patients, aged 9.2 to 18 years, and 40 healthy females, aged 9.3 to 18 years, as the control group. The TS patients were subdivided according to karyotype. All study participants were evaluated cephalometrically. An analysis of variance (ANOVA) and Tukey's multiple comparison test were used for analysis of the differences between the means in Turner subgroups and the control group.Results: In general, the girls with TS were characterized by smaller dimensions and an altered morphology of the craniofacial complex compared with the unaffected girls. The curvature of the frontal bone was significantly increased, while the diameter of the head was reduced. Both the maxilla and mandible were retrognathic, posteriorly rotated, and reduced in antero-posterior length. The cranial base was shorter and flattened. Among the different karoytypes, no significant differences were determined in the dimensions of the craniofacial complex in girls with TS. Conclusions:Our findings indicate that the karyotype has no effect on craniofacial morphology and we confirmed that a specific model of craniofacial morphology in individuals with TS is present in early childhood. is approximately one in 2,500 girls. 4 Several karyotypes responsible for the syndrome have been identified, the most common being monosomy X, found in about 50-60% of the girls. Less common are the mosaic and isochromosome for the long arm of the X chromosome.5,6 Short stature, gonadal dysgenesis, pterygium colli, cubitus valgus, and low hairline at the back of the neck are the most common features of this disease. 7The smaller size of teeth in individuals with TS 8-12 is caused by reduced enamel thickness. 13,14 Females with TS have a tendency toward distal molar occlusion, lateral crossbite, and open bite. 8,15,16 Skeletal maturity was retarded by an average of 2.2 years